How to remove your Cozi.com account
Send a removal request (with your user name) to: firstname.lastname@example.org. By the way, we could not find this info on their site. Shame.
Helpful Trick: Removing online data
Helpful Trick: Remove third-party logins
If you signed up for Cozi.com using a third-party login such as Facebook or Twitter, you probably want to revoke all access from Cozi.com. Click here to find out how.